According to the U.S. Census Bureau, the parish has a total area of 1,299 square miles (3,360 km2), of which 1,252 square miles (3,240 km2) is land and 47 square miles (120 km2) (3.6%) is water.[4] It is the fourth-largest parish by land area in Louisiana. The primary groundwater resources of Natchitoches Parish, from near surface to deepest, include the Red River alluvial, upland terrace, Sparta, and Carrizo-Wilcox aquifers.[5]

There were 14,263 households out of which 33.00% had children under the age of 18 living with them, 45.30% were married couples living together, 17.70% had a female householder with no husband present, and 33.40% were non-families. 27.10% of all households were made up of individuals and 10.90% had someone living alone who was 65 years of age or older. The average household size was 2.56 and the average family size was 3.14.

In the parish the population was spread out with 26.00% under the age of 18, 17.90% from 18 to 24, 24.30% from 25 to 44, 19.70% from 45 to 64, and 12.10% who were 65 years of age or older. The median age was 30 years. For every 100 females there were 90.60 males. For every 100 females age 18 and over, there were 85.80 males.

The median income for a household in the parish was $25,722, and the median income for a family was $32,816. Males had a median income of $29,388 versus $19,234 for females. The per capita income for the parish was $13,743. About 20.90% of families and 26.50% of the population were below the poverty line, including 32.70% of those under age 18 and 19.00% of those age 65 or over.

The last Democrat to win in Natchitoches Parish at the presidential level was Bill Clinton in 1996, who received 8,296 votes (54.7 percent), compared to Republican Robert J. Dole's 5.471 ballots (36.1 percent). Ross Perot of the Reform Party held 1,053 votes (6.9 percent).[15]

A Troop 2-108TH CAV is headquartered in behind the local college and the airport. This unit has deployed twice to Iraq, first as part of the 1-156TH Armor Battalion in 2004-2005 and then as part of the 2-108TH CAV SQDN in 2010. Both times this company sized element deployed with the 256th Infantry Brigade.

William Tharp Cunningham (1871-1952), planter, lawyer, judge of the 11th Judicial District in Natchitoches and Red River parishes, member of the Louisiana House of Representatives from 1908 to 1912, born in Natchitoches Parish in 1871[21]

Caroline Dormon (1888–1971), naturalist, botanist, and preservationist (1888–1971) was born and lived on her family estate of Briarwood in Natchitoches Parish.

Brothers J. Isaac Friedman (1877-1949) and Leon Friedman (1886-1948) served in the Louisiana House from 1908 to 1916 and 1932 to 1940, respectively. Isaac Friedman also served an abbreviated term in the state Senate from 1922 to 1924, following the resignation of Charles Milton Cunningham. Their nephew, Sylvan Friedman was a member of both houses of the state legislature, the House from 1944 to 1952, and the state senate from 1952 to 1972. The Friedmans came from a large Jewish landholding family in Natchez in south Natchitoches Parish.

Andrew R. Johnson (1856–1933), Louisiana state senator and former mayor of Homer, Louisiana, in 1901 named and sold lots to establish the village of Ashland in Natchitoches Parish.[22]